JP-A 10-181635 discloses a vehicle body side unit. In the conventional body side unit, a vertically oriented front door latch pillar is provided for joining a roof stringer to a lower lengthwise member of the vehicle, such as, a floor side sill member. This body side unit is formed of light metal alloy by casting. The vehicle body constructed by such body side unit is advantageous over a vehicle body constructed by a great number of elements formed by pressing in reduction of number of working processes and reduction of cost.
The above-mentioned vehicle body is satisfactory to certain extent. However, a need remains to improve distribution of strength and rigidity, and to accomplish further reduction in cost and weight.
Accordingly, an object of the present invention is to provide a motor vehicle body structure that has optimum distribution of strength and rigidity with reduced cost and weight.